GB2041650A

GB2041650A - Fluid level monitoring device

Info

Publication number: GB2041650A
Application number: GB7938841A
Authority: GB
Original assignee: Messmer Werner Co KG GmbH
Current assignee: Messmer Werner Co KG GmbH
Priority date: 1979-01-16
Filing date: 1979-11-09
Publication date: 1980-09-10
Also published as: GB2041650B; SE7908573L; FR2447014A1; ES485862A1; DE2901532A1; DE2901532C2

Abstract

A fluid level monitoring device is provided which comprises a float 4, which is pivotally mounted in a portion of a housing 3 and carries a magnet in a mounting zone within the container 1. The device includes a contact closing element, which cooperates with the magnet and two contacts mounted in the housing. A portion of the housing projects from the container and has arranged therein contact connection pieces connected to the contacts. The mounting zone (11) of the float (4) is secured through a swivel pin (12) to a portion (5) of the housing (3) which projects into the container (1). The mounting zone (11) comprises two surfaces (13, 14) which are at an angle to each other, the magnet (15) being mounted in one surface (14). <IMAGE>

Description

SPECIFICATION Fluid level monitoring device The invention relates to a fluid level monitoring device comprising a float, which is provided inside a container and which is pivotally mounted in a portion of a housing that projects into the container and which comprises a magnet in the mounting zone, and comprising a contact closing element, which co-operates with the magnet and two contacts and which is mounted in the housing, and comprising a housing portion which projects from the container and in which there are arranged contact connection pieces which are connected to the contacts.

There is already known as the prior art level monitoring device wherein the mounting zone of the float is designed as a ball and is mounted in a ball cage. When the fluid level inside the container drops, the float swivels around the ball-shaped mounting zone downwards, which causes a magnet in the mounting zone to enter the range of influence of a ball and to move this ball away from two contacts, thus causing one contact to be disconnected.

In this known arrangement, the ball-shaped mounting zone is disadvantageous since this does not allow an exactly defined swivelling of the float to be carried out. Consequently, it is possible, for example, for the magnet unintentionally to enter the range of influence of the contact closing element, namely the ball, and thus to trigger an indicating action which is not intended. This known device therefore does not ensure a faultless indicating function.

The prior art furthermore includes level monitoring devices wherein, being guided perpendicularly, a float is movable vertically, the movement of the float causing a magnet to pass into the range of influence of a switch and by this means to trigger an indication. This known device is relatively complicated in construction and necessitates a large number of individual components, which makes the device as a whole expensive.

The object of the present invention is to provide a level monitoring device of the kind mentioned at the beginning which, while simple in construction, ensures a faultless indication.

According to the invention, this problem is solved in that the mounting zone of the float is secured through a swivel pin to that portion of the housing which projects into the container and in that the mounting zone comprises two surfaces which are at an angle to each other, the magnet being mounted on one surface. This results in the advantage that the swivel pin ensures a clearly defined swivel movement of the float so that the functional reliability of the device is increased. Furthermore, malfunctions of the contact closing element are avoided due to the surfaces which are arranged angularly to each other in the mounting zone.

According to another feature of the invention, the swivel pin is arranged so as to be horizontal. The front end of the housing portion that projects into the container is U-shaped in design, the mounting zone of the float being arranged between the two legs of the front end and the swivel pin passing through the two legs and the mounting zone. By this means, there is provided a simple but very effective mounting of the float on the housing.

According to another feature of the invention, the swivel pin may be arranged so as to be transverse to the longitudinal axis of the housing in the horizontal plane thereof. In a further development of the invention, the float may comprise above and below the mounting zone limiting stops which co-operate with the front end of the housing. By this means, the swivel range of the float is advantageously limited.

According to another feature of the invention, the two surfaces of the mounting zone which are at an angle to each other are directed in a wedge-shaped manner towards the connecting part connecting the two legs of the housing front end. The magnet is advantageously arranged to the lower-surface so that, when the float is lowered as a result of the absence of fluid inside the container, the magnet passes into the range of the contact closing element.

This contact closing element may be designed as a ball so that, if there is a shortage of fluid in the container, the ball closes the two contacts due to the action of the magnet arranged in the mounting zone of the float. This ensures a faultless indication.

In a further development of the invention, the housing, in which the float, the contacts and the contact connection pieces are mounted, may be separate from the container and may be positively fastened to the container. This fastening may be effected, for example, through clips, a bayonet fixing or screws. In any event, a rapid assembly is provided.

On the other hand, it is also possible to form the housing integrally with the container. This obviates any sealing requirements between the container and the housing.

In a further development of the invention, the container, the housing and the float may consist of plastics material.

The invention will hereinafter be described in more detail with reference to an exemplified embodiment illustrated in the drawing. The drawing shows a cross section through a container provided with the level monitoring device.

As shown in the drawing, the level monitoring device 2 is provided in the container 1 which is filled with a fluid. This device 2 substantially consists of a housing 3 having a portion 5 which projects into the container and a portion 6 which projects from the container. The portion 5 of the housing 3 projecting into the container is of U-shaped- design at the front end, a float 4 engaging with its mounting zone 11 between the two legs of the U-sh'aped portion of the front end 16. A swivel pin 12, which is arranged so as to be transverse to the longitudinal axis of the housing 3 in the horizontal plane thereof, passes through the two legs of the front end 16 of the housing 3 as well as through the mounting zone 11 of the float 4.

The mounting zone 11 comprises two surfaces 13 and 14 which are at an angle to each other and which are directed towards the connecting part 8 at the front end 16 of the housing 3.

Inside the housing 3, there is provided as the contact closing element a ball 9 which is mounted inside a cage 20. In its front zone, the cage 20 is shut by two contacts 7 and 8. These two contacts 7 and 8 are in communication with contact connection pieces 10 in the portion 6 of the housing 3 projecting from the container.

The front end 16 of the housing 3 comprises in the zone of the connecting part 18, on top thereof, a limiting stop 17 which, as the float 4 moves in the direction of the arrow II, co-operates with the surface 13 of the mounting zone 11 and thus limits the pivotability of the float 4 round the swivel pin 12. A fluid is provided in the container 1. Consequently, the float 4 is at first located approximately in the horizontal position shown in solid lines in the drawing or it has been swivelled in the direction of the arrow I. If the fluid level drops, then the float 4 swivels round the pin 12 in the direction of the arrow II, which causes the surface 14 of the mounting zone 11 to be increasingly placed into an approximately vertical position.By this means, the magnet 15, which is embedded in the surface 14 of the mounting zone 11, enters the range of action of the contact closing elementformed as the ball 9. Due to the action of the magnet 15, the ball 9 is lifted, which causes a connection between the contacts 7 and 8 to be produced with the aid of the ball 9. This connection causes the contacts to be closed, which is transmitted through the contact connection pieces 10 so thatthis causes, for example, a warning lamp, which is not shown in detail, to light up and to indicate that there is not enough fluid in the container 1.

Instead of the limiting stop 17 shown in the drawing, it is also possible to provide limiting stops above and below the mounting zone 11, which co-operate with the front end 16 of the housing 3 (not shown in detail). The swivel pin 12 is at right angles to the longitudinal axis of the housing 3 in the horizontal plane thereof, whereby an exactly defined swivel movement of the float 4 and thus a high functional reliability is provided.

The housing 3 may comprise a flange 19 on the portion 6 projecting from the container, whereby a good contact with the container 1 is provided. The fastening of the housing 3 to the container 1 may be effected, for example, by way of a screw of clip connection.

Another possibility consists in that the housing 3 and the container X are integrally formed, both parts being supplied to the final user as a completely assembled unit. This obviates an additional assembly and adjustment of the level monitoring device 2 by the final user, for example a motor car factory.

The container 1, the housing 3 and the float 4 may consist of plastics material. The float 4 may be made from a cylindrical tube which is shut at the end by a flat plate and in the front zone by a part forming the mounting zone 11.

The mounting zone 11 of the float 4 -6omprises-the two surfaces 13 and 14which are at an angle to each other; in the exemplified embodiment shown in the drawing, this is an angle of approximately 90". If the float 4 is in its normal horizontal position shown in the drawing, then, since the magnet 15 is embedded in the lower surface 14, it is reliably avoided that the ball 9 causes the two contacts 7 and 8 to be closed, since the magnet 15 is not in any event within the range of action of the ball 9.

In all, there is provided a level monitoring device which is of simple construction but is very effective and which ensures that the float will swivel without any trouble about an exactly defined axis, namely the swivel pin 12, and which, on the other hand, prevents the magnet 15 from unintentionally entering the range of action of the ball 9.

Claims

1. Afluid level monitoring device comprising a float, which is provided inside a container and which is pivotally mounted in a portion of a housing that projects into the container and which comprises a magnet in the mounting zone, and comprising a contact closing element, which co-operates with the magnet and two contacts and which is mounted in the housing, and comprising a housing portion which projects from the container and in which there are arranged contact connection pieces connected to the contacts, characterised in that the mounting zone of the float is secured through a swivel pin to the portion of the housing which projects into the container and in that the mounting zone comprises two surfaces which are at an angle to each other, the magnet being mounted in one surface.

2. A device as claimed in Claim 1, characterised in that the swivel pin is arranged so as to be horizontal.

3. A device as claimed in Claims 1 and 2, characterised in that the front end of the portion of the housing projecting into the container is of U-shaped design and in that the mounting zone of the float is arranged between the two legs of the front end, the swivel pin -passing through the two legs and the mounting zone.

4. A device as claimed in Claim 3, characterised in that the swivel pin is arranged so as to be transverse to the longitudinal axis of the housing in the horizontal plane thereof.

5. A device as claimed in Claim 3, characterised in that above and belowthe mounting zone, the float comprises limiting stops which co-operate with the front end of the housing.

6. A device as claimed in Claim 1, characterised in that the two surfaces of the mounting zone which are at an angle to each other are directed in a wedge-like manner towards the connecting part connecting the two legs of the housing front end.

7. A device as claimed in Claims 1 and 6, characterised in that the magnet is arranged on the lower surface.

8. A device as claimed in Claim 1 and provided with a ball which is designed as the contact closing element, characterised in that if there is a shortage of fluid in the container, the ball closes the two contacts due to the action of the magnet arranged in the mounting zone ofthe float.

9. A device as claimed in one of the preceding Claims, characterised in that the housing, in which the ball, the float, the contacts and the contact connection pieces are mounted, is formed separately from the container and is positively secured to the container.

10. A device as claimed in one of Claims 1 to 8, characterised in that the housing, in which the ball, the float, the contacts and the contact connection pieces are mounted, is formed integrally with the container.

11. A device as claimed in one of the preceding Claims, characterised in that the container, the housing and the float consist of plastics material.

12. A device as claimed in Claim 1 and provided with a ball which is designed as the contact closing element, characterised in that if there is a shortage of fluid in the container, the ball opens the two contacts due to the action of the magnet arranged in the mounting zone of the float.

13. A fluid level monitoring device substantially as described with reference to the accompanying drawings.